Same as CFs only a better design, not being folded they do a better job at getting the light where it's needed using reflectors. Other than that, they are too expensive at the moment in the US, you always pay for novilty, but in time they will be cheap and a bigger selection of bulbs will be available. In Italy I noticed these for sale in hardware stores as shop lights, so you can imagine how cheap they will become in time. I'm sure they'll replace most of the T8 lighting over time, just like T8 replaced much of the T12 lighting fixtures.
Hope that helps
Giancarlo Podio
Hope that helps
Giancarlo Podio